<ul>
    <foreach name="list" item="v" key="k">
        <li>
            <span class="tree_span" data-tab="{$v[user_level]}" data-id="{$v[user_id]}">
                 <i class="icon-folder-open"></i>
                 {$v['user_id']}:
                 <if condition="$v['nickname'] neq null">
                     {$v['nickname']}
                     <elseif condition="$v['mobile'] neq null"/>
                     {$v['mobile']}
                     <elseif condition="$v['email'] neq null"/>
                     {$v['email']}
                 </if>
             </span>
        </li>
    </foreach>
</ul>